has anyone done anything similar?was wondering how long it might take, routes, high viewpoints, etc, advice or if it might be too wet in early sept this year to go in that way.it looks like there is a trail up to smiths peak. ive never been to the hetchy area i figured this year i might check it out.thanks in advance

There is a trail up to Smith Peak, yes. And then you hike in forest to harden lake, not terribly many views unless you leave the trail. Early September this area will be dry.

Are you thinking that you will hike on the road from the entrance station to Hetch Hetchy? There's no trail down to it. Sounds hot, hot, hot, hot and hot. Kind of dangerous given how narrow the road gets and how people drive on it.

good to know, thanks, i was assuming if WW campground is open , then i would be good to drive inand park up the road somewhere.i may even camp there a couple nights so i figured why drive around when i could start to to hike in from there.

Since the road ends at the campground/resort there's no real point in parking along the road... there is trailhead parking. You'll have to get the wilderness permit at one of the wilderness offices before you go to WW, they do not issue them there. Also the resort closes in mid September, and so then the road will be gated at the highway.

Harden Lake will be bone dry by then. It's a shallow lake in low spot between two glacial moraines that drains off fast. Not many views, except for Smith Peak, which has a trail to the summit, but a steep, brushy, dry, hot one. All in all, the trip down to Hetch Hetchy/Mather is pretty unfulfilling, and if you plan to climb back up to WW, it's about 1800 feet of hot and exposed ascent on the lower portion for not much reward in return. If you want a great view aside from a dayhike (sans pack) up to Smith Peak, take a side trip for an overnight at the ledges at the top of Morrison Creek, then backtrack to Harden and do a loop over to Cottonwood Creek towards Aspen Valley, then return to WW along the Middle Fork of the Tuolumne River. Generally forested and shady, good water for a good part of the route, not a very crowded part of the park due to not many views. Although it is interesting and worth checking out.

The parking up at the camp tends to be crowded, but if so, the rangers are pretty good about letting you park along the road next to the campground if you ask them and need to.

Oh, and Smith Meadow is 8.3 miles to the junction from White Wolf, and Smith Peak is another 1.5 miles up from there, FYI. Water is at Cottonwood Creek that time of year. If you want to use the Tom Harrison 1:63,360 maps, you'll need a combination of the Yosemite High Country and Hetch Hetchy area maps in that series. If 1:125,000 is good enough, it's all shown on their Yosemite National Park version.